1. Field of the Invention
The present invention relates to an apparatus and a method of inspecting a foreign particle or a defect on a sample. More specifically, the present invention relates to an apparatus and a method of inspecting a foreign particle or a defect on a sample in which a foreign particle present on a substrate and a defect caused on a circuit pattern are detected and displayed so that the cause of failure can be corrected.
2. Prior Art
Conventionally, a technology of detecting a defect on a wafer or the like by optical measuring means has been widely known. For example, according to Japanese Patent Laid-Open No. S62-89336 xe2x80x9cSemiconductor wafer inspecting apparatusxe2x80x9d, there is disclosed a technology of irradiating laser onto a wafer and inspecting a defect by detecting scattered light from a foreign particle generated when the foreign particle is adhered onto the wafer and comparing a result of detection with that of a wafer of the same kind inspected immediately before the detection.
Further, according to Japanese Patent Laid-Open No. H5-273110 xe2x80x9cMethod and apparatus of measuring size information of particle or defectxe2x80x9d, there is disclosed a method of measuring a size of a particle or a crystal defect by irradiating an object to be detected with laser beam, receiving scattered light from a particle or a crystal defect of the object to be detected and subjecting the received light to image processing.
Conventionally, in a fabrication line of a wafer, or a substrate for forming a thin film or the like, an inspection system has been used for inspecting a foreign particle or a pattern defect on a substrate and monitoring a transitional change of the number of detection from the foreign particle or defect inspection system and providing a failure analysis on a substrate having a large number of detection with respect of foreign particles or defects on the substrate.
However, according to the conventional technology, a time period required for failure analysis is constituted by xe2x80x9cthe number of detection multiplied by a failure analysis time period with respect to one foreign particle or defectxe2x80x9d. In particular, when the number of detection is large in the foreign particle or defect inspection system, an enormous time period is required for failure analysis. As a result, the fabrication of substrates can be delayed significantly.
It is an object of the present invention to provide a method of inspecting a foreign particle or a defect on a sample and a system thereof capable of carrying out inspection in accordance with a size of a foreign particle or a size of a defect and characteristics of areas of an object to be inspected during a fabrication procedure and providing failure analysis of an object such as a semiconductor wafer or a substrate for forming a thin film.
According to an embodiment of the present invention, a method of inspecting a foreign particle or a defect may be carried out by a procedure of irradiating light to the object to be inspected, a procedure of detecting reflected light or scattered light from the object to be inspected, a procedure of detecting the foreign particle or the defect based on a detected signal, a procedure of carrying out a signal processing based on the detected signal and measuring a size of the foreign particle or the defect, a procedure of processing data for processing a result of inspection and a procedure of displaying information of the result of inspection in this order, the size of the foreign particle or the defect is correlated with failure cause, in the data processing procedure, the failure cause is indicated from a statistical processing of the result of inspection and information of the result of inspection is displayed.
According to the present invention, in carrying out inspection of a fabrication procedure and failure analysis of a semiconductor wafer or a substrate for forming a thin film, there can be provided a method of inspecting a foreign particle or a defect and its system capable of carrying out swift failure countermeasure by carrying out the inspection and the failure analysis in accordance with characteristics of the foreign particle or pattern and characteristics of areas of the object to be inspected.